One very important thing you can do for your child's speech and language development is to READ.
Read to your child. Read with you child. Have your child read or pretend to read. Don't be afraid to read the same books over and over again.
When you read predictable, age-appropriate books to a child, you provide the opportunity to hear the sounds and structure of language over and over which is how children learn best. Having a child name objects in a book or read aloud to you can strengthen her ability to organize words and thoughts.
Reading aloud to young children is one of the best activities to stimulate language and cognitive skills; it also builds motivation, curiosity, and memory. (Bardige, B. Talk to Me, Baby!(2009), Paul H Brookes Pub Co.)